Calibration system and calibration bracket thereof

ABSTRACT

The present invention relates to the field of vehicle correction, and provides a calibration system and a calibration bracket thereof. The calibration bracket includes: a base, a stand assembly and a beam assembly. The stand assembly is fixedly connected to the base. The beam assembly includes a first beam portion, a second beam portion and a connecting portion, the connecting portion being mounted to the stand assembly, one end of the connecting portion being hinged to the first beam portion, and the other end of the connecting portion being hinged to the second beam portion. The first beam portion and the second beam portion can respectively rotate toward each other relative to the connecting portion, so that the beam assembly can be folded. The first beam portion and the second beam portion can also respectively rotate away from each other relative to the connecting portion, so that the beam assembly can be unfolded. In the foregoing structure, the first beam portion and the second beam portion can respectively rotate toward each other relative to the connecting portion, so that the beam assembly is folded, thereby reducing a volume of the calibration bracket to facilitate shipment.

This application is a continuation of U.S. patent application Ser. No.17/109,683 filed on Dec. 2, 2020, which is a continuation ofInternational Patent Application No. PCT/CN2020/073838 filed on Jan. 22,2020, which claims priority to Chinese Patent Application No.201910105255.7 filed on Feb. 1, 2019, both of which are incorporated byreference herein in their entireties.

BACKGROUND Technical Field

The present application relates to the technical field of vehiclemaintenance and device calibration, and in particular, to a calibrationsystem and a calibration bracket thereof.

Related Art

An advanced driver assistant system (ADAS for short) is an activesecurity technology that is used to collect environmental data insideand outside a vehicle at the first time using various sensors mounted tothe vehicle to perform technical processing such as identification,detection, and tracking of static and dynamic objects, so that a drivercan detect a possible danger as quickly as possible, thereby attractingattention and improving safety. A sensor used in the ADAS mainlyincludes a camera, radar, a laser, and an ultrasonic wave, which may beused to detect light, heat, pressure, or other variables for monitoringa state of the vehicle, and is usually located on front and rearbumpers, on a side mirror, inside a steering column, or on a windscreenof the vehicle. During the use of the vehicle, vibration, collision,environmental temperature and humidity, and the like will change thephysical mounting status of the sensor, and therefore irregularcorrection or calibration is required.

When the foregoing sensor is corrected or calibrated, calibrationelements are usually mounted to the calibration bracket to correct orcalibrate the sensor on the vehicle. However, most of the currentcalibration brackets are relatively large, occupy a relatively largearea, are complicated to assemble, and are difficult to move.

SUMMARY

Embodiments of the present invention are intended to provide acalibration system and a calibration bracket thereof, which can solvethe technical problem that a calibration element is difficult to move inthe prior art.

In the embodiments of the present invention, the technical problem isresolved by using the following technical solutions.

A calibration bracket is provided, including:

a base;

a stand assembly fixedly connected to the base; and

a beam assembly including a first beam portion, a second beam portionand a connecting portion, the connecting portion being mounted to thestand assembly, one end of the connecting portion being pivotallyconnected to the first beam portion, and the other end of the connectingportion being pivotally connected to the second beam portion.

Optionally, the stand assembly includes a fixed vertical rod and amovable vertical rod,

one end of the fixed vertical rod being mounted to the base;

the movable vertical rod being arranged in the fixed vertical rod andbeing capable of moving only along a length direction of the fixedvertical rod relative to the fixed vertical rod; and

the beam assembly being mounted to the movable vertical rod.

Optionally, cross-sections of the fixed vertical rod and the movablevertical rod are non-circular.

Optionally, one of the fixed vertical rod and the movable vertical rodincludes a guide rail, the other being guided by the guide rail to moveonly along the length direction of the fixed vertical rod.

Optionally, the beam assembly includes a mounting seat, the connectingportion being arranged in the mounting seat and mounted to the standassembly through the mounting seat; and

the mounting seat being provided with a fixing rod, the fixing rodincluding at least one section of screw rod, so that the fixing rod canbe screwed to press the connecting portion on the mounting seat.

Optionally, one of the mounting seat and the connecting portion includesat least one positioning column, and the other includes at least onepositioning hole, the at least one positioning column being insertedinto the at least one positioning hole to position the connectingportion in the mounting seat.

Optionally, the fixing rod is at an angle to a horizontal direction, sothat the connecting portion is pressed on a bottom surface and one sidesurface of the mounting seat, the angle being greater than 0 degree andless than 90 degrees.

Optionally, the angle is 45 degrees.

Optionally, the beam assembly includes an adjustment mechanism connectedto the mounting seat and configured to adjust a horizontal angle of themounting seat and the connecting portion.

Optionally, the adjustment mechanism includes a first elastic member, arotating member and an adjusting rod,

the rotating member being connected to the mounting seat, and therotating member being capable of rotating around an adjustment rotationaxis relative to the mounting seat, the adjustment rotation axis beingarranged vertically;

one end of the first elastic member being fixed to the mounting seat,and the other end being fixed to the rotating member; and

the adjusting rod being mounted to the mounting seat and being inscrew-thread fit with the mounting seat;

the adjusting rod being rotated, so that the adjusting rod pushes themounting seat to rotate around the adjustment rotation axis relative tothe rotating member, and the horizontal angle of the mounting seat andthe connecting portion can be adjusted; and

the adjusting rod being rotated, so that the adjusting rod is away fromthe mounting seat, and the mounting seat can be pulled, by using thefirst elastic member, to rotate and reset around the adjustment rotationaxis relative to the rotating member.

Optionally, the adjustment mechanism includes a supporting shaft and abearing seat,

the supporting shaft being fixedly mounted to the mounting seat, and acentral axis of the supporting shaft overlapping with the adjustmentrotation axis;

the rotating member being sleeved on the bearing seat; and

the supporting shaft being inserted into the bearing seat, and thesupporting shaft and the mounting seat being capable of rotatingtogether around the adjustment rotation axis relative to the rotatingmember and the bearing seat.

Optionally, the stand assembly includes a driving mechanism mounted tothe fixed vertical rod and configured to drive the movable vertical rodto move along a length direction of the fixed vertical rod relative tothe fixed vertical rod.

Optionally, the driving mechanism includes a gear reduction assembly.

Optionally, the stand assembly includes a driving mechanism mounted tothe fixed vertical rod and configured to drive the movable vertical rodto move along a length direction of the fixed vertical rod relative tothe fixed vertical rod, the driving mechanism including a rack, ahousing, a worm, a worm gear and a second transmission gear,

the rack being fixedly mounted to the movable vertical rod, beingarranged along a length direction of the movable vertical rod, andforming the guide rail;

the housing being fixedly mounted to the fixed vertical rod;

the worm being engaged with the worm gear;

the worm gear being fixedly mounted to the second transmission gear, arotation axis of the worm gear overlapping with a rotation axis of thesecond transmission gear, and the worm gear and the second transmissiongear being capable of rotating around a third rotation axis; and

the second transmission gear being fixedly mounted to the housing andbeing engaged with the rack;

the third rotation axis being perpendicular to the rack.

Optionally, the stand assembly includes a fastening mechanism and anelastomer,

the fastening mechanism being mounted to the fixed vertical rod andconfigured to fix the movable vertical rod to the fixed vertical rod,and

the elastomer being connected between the bottom of the fixed verticalrod and the movable vertical rod and being in a compressed state.

Optionally, the beam assembly includes at least one supporting rodconfigured to support a target to prevent falling.

Optionally, the supporting rod is pivotally connected to one of thefirst beam portion, the second beam portion and the connecting portion.

Optionally, at least one of the first beam portion, the second beamportion and the connecting portion includes a supporting rod guide rail,the supporting rod being supported by the supporting rod guide rail andbeing capable of moving along the supporting rod guide rail.

Optionally, the supporting rod includes a supporting rod body and asupporting member, the supporting rod body being provided with a slot,at least one of the first beam portion, the second beam portion and theconnecting portion being provided with a fixture block, or at least oneof the first beam portion, the second beam portion and the connectingportion being provided with a slot, and the supporting rod body beingprovided with a fixture block,

the fixture block being engaged into the slot to engage the supportingrod with the at least one of the first beam portion, the second beamportion and the connecting portion.

Optionally, the beam assembly includes a first fastener and a secondfastener,

one end of one of the first beam portion and the connecting portionbeing hinged to one first fastener, one end of the other being providedwith one second fastener, and the first fastener and the second fastenerbeing fastened to each other to fasten the first beam portion to theconnecting portion.

Optionally, the beam assembly includes at least one joint mechanismconnected between the first beam portion and the connecting portion orbetween the second beam portion and the connecting portion.

Optionally, the joint mechanism includes a first fixing member and asecond fixing member,

the first fixing member including a fastening member, a rotating shaftand a second elastic member, the rotating shaft being fixedly connectedto an inner wall of the first fixing member, the fastening member beingmounted to the rotating shaft, being capable of rotating around therotating shaft, and including a first end and a second end, the firstend and the second end being respectively located at two ends of therotating shaft, and the second elastic member being connected to theinner wall of the first fixing member and the first end of the fasteningmember; and

the second fixing member including a locking protrusion, the lockingprotrusion being mated with the second end of the fastening member andbeing engaged with the fastening member under the action of the secondelastic member.

Optionally, the joint mechanism further includes a screwing mechanism,the screwing mechanism passing through the first fixing member and beingscrewed to abut against the first end of the fastening member, so thatthe first end can be fastened to the locking protrusion.

Optionally, the joint mechanism further includes a button, and thesecond end of the fastening member includes a bump,

the button passing through the second fixing member and being capable ofabutting against the bump in a pressed state, so that the lockingprotrusion can be separated from the fastening member.

The embodiments of the present invention further adopt the followingtechnical solution to resolve the technical problem.

A calibration bracket is provided, including:

a base;

a fixed vertical rod, one end of the fixed vertical rod being mounted tothe base;

a movable vertical rod arranged in the fixed vertical rod and capable ofmoving only along a length direction of the fixed vertical rod relativeto the fixed vertical rod; and

a foldable beam assembly mounted to a top surface of the movablevertical rod.

Optionally, the beam assembly includes a beam, an adjustment mechanismand a mounting seat, the beam being disposed in the mounting seat, themounting seat being disposed on the adjustment mechanism, and theadjustment mechanism being configured to adjust a horizontal angle ofthe beam.

The embodiments of the present invention further adopt the followingtechnical solution to resolve the technical problem.

A calibration bracket is provided, including:

a base;

a stand assembly fixedly connected to the base; and

a foldable beam assembly mounted to the stand assembly and including abeam, the beam including at least two parts, the at least two partsbeing connected through a joint mechanism, so that the at least twoparts can be pivotally connected.

Optionally, the joint mechanism includes a first fixing member and asecond fixing member,

the first fixing member including a fastening member, a rotating shaftand a second elastic member, the rotating shaft being fixedly connectedto an inner wall of the first fixing member, the fastening member beingmounted to the rotating shaft, being capable of rotating around therotating shaft, and including a first end and a second end, the firstend and the second end being respectively located at two ends of therotating shaft, and the second elastic member being connected to theinner wall of the first fixing member and the first end of the fasteningmember; and

the second fixing member including a locking protrusion, the lockingprotrusion being mated with the second end of the fastening member andbeing engaged with the fastening member under the action of the secondelastic member.

Optionally, the joint mechanism further includes a screwing mechanism,the screwing mechanism passing through the first fixing member and beingscrewed to abut against the first end of the fastening member, so thatthe first end can be fastened to the locking protrusion.

The embodiments of the present invention further adopt the followingtechnical solution to resolve the technical problem.

A calibration bracket is provided, including:

a base;

a stand assembly fixedly connected to the base;

a foldable beam; and

a mounting seat, the beam being disposed in the mounting seat, themounting seat being provided with a fixing rod, the fixing rod beingconfigured to press the beam on the mounting seat and being at an angleto a horizontal direction, the angle being greater than 0 degree andless than 90 degrees.

Optionally, the angle is 45 degrees.

Optionally, the fixing rod includes at least one section of screw rod,so that the fixing rod can be screwed to press the beam on the mountingseat.

The embodiments of the present invention further adopt the followingtechnical solution to resolve the technical problem.

A calibration system includes a calibration element and the foregoingcalibration bracket, the calibration element being mounted to thecalibration bracket.

Compared with the prior art, in the calibration bracket of the presentembodiment, the first beam portion and the second beam portion canrespectively rotate toward each other relative to the connectingportion, so that the beam assembly is folded, thereby reducing a volumeof the calibration bracket to facilitate shipment.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments are described by way of example with referenceto the corresponding figures in the accompanying drawings, and thedescriptions are not to be construed as limiting the embodiments.Elements in the accompanying drawings that have same reference numeralsare represented as similar elements, and unless otherwise particularlystated, the figures in the accompanying drawings are not drawn to scale.

FIG. 1 is a three-dimensional view of a calibration bracket according toan embodiment of the present invention, where a multi-line laser ismounted to the calibration bracket.

FIG. 2 is a three-dimensional view of the calibration bracket shown inFIG. 1 from another perspective.

FIG. 3 is a three-dimensional view of the calibration bracket shown inFIG. 1 , where a beam assembly of the calibration bracket is in a foldedstate.

FIG. 4 is a three-dimensional view of a stand assembly of thecalibration bracket shown in FIG. 1 .

FIG. 5 is a three-dimensional view of the stand assembly shown in FIG. 4, where some elements are omitted.

FIG. 6 is a three-dimensional view of a stand assembly according to someembodiments, where some elements are omitted.

FIG. 7 is a three-dimensional view of a stand assembly according to someother embodiments.

FIG. 8 is an exploded view of a stand assembly shown in FIG. 7 .

FIG. 9 is a three-dimensional view of a beam assembly of the calibrationbracket shown in FIG. 1 .

FIG. 10 is a cross-sectional view of the beam assembly shown in FIG. 9 .

FIG. 11 is an exploded view of the beam assembly shown in FIG. 9 .

FIG. 12 is a partial enlarged diagram of a portion A in FIG. 9 ;

FIG. 13 is an exploded view of an adjustment mechanism of the beamassembly shown in FIG. 9 .

FIG. 14 is an exploded view of the adjustment mechanism shown in FIG. 13from another perspective.

FIG. 15 is a three-dimensional view of a joint mechanism of the beamassembly shown in FIG. 9 .

FIG. 16 is a three-dimensional view of the joint mechanism shown in FIG.15 from another perspective.

FIG. 17 is a cross-sectional view of the joint mechanism shown in FIG.15 .

FIG. 18 is a three-dimensional view of a joint mechanism according tosome embodiments.

FIG. 19 is a cross-sectional view of the joint mechanism shown in FIG.18 .

FIG. 20 is a three-dimensional view of a first fastener and a secondfastener fastened to each other according to some embodiments.

FIG. 21 is a three-dimensional view of a calibration system according toanother embodiment, where the calibration system includes a calibrationbracket and a calibration element, the calibration element being areflector mounted to the calibration bracket.

FIG. 22 is a three-dimensional view of a calibration system shown inFIG. 21 , where the reflector is replaced with a pattern plate mountedto the calibration bracket.

DETAILED DESCRIPTION

To facilitate the understanding of the present invention, the presentinvention is further described below in further detail with reference tothe accompanying drawings and specific embodiments. It is to be notedthat, when an element is described to be “fixed on” another element, itmay be directly fixed on the other element, or there may be one or moreintermediate elements between them. When an element is described to be“connected to” another element, it may be directly connected to theother element, or there may be one or more intermediate elements betweenthem. In the description of this specification, orientation or positionrelationships indicated by the terms such as “up”, “down”, “inside”,“outside”, “vertical”, and “horizontal” are based on orientation orposition relationships shown in the accompanying drawings, and are usedonly for ease and brevity of illustration and description of the presentinvention, rather than indicating or implying that the mentionedapparatus or component needs to have a particular orientation or needsto be constructed and operated in a particular orientation. Therefore,such terms should not be construed as limiting of the present invention.In addition, terms “first” and “second” are only used to describe theobjective and cannot be understood as indicating or implying relativeimportance.

Unless otherwise defined, meanings of all technical and scientific termsused in the present invention are the same as that usually understood bya person skilled in the art to which the present disclosure belongs.Terms used in the specification of the present invention are merelyintended to describe objectives of the specific embodiments, but are notintended to limit the present invention. A term “and/or” used in thepresent invention includes any or all combinations of one or morerelated listed items.

In addition, the technical features involved in the differentembodiments of the present invention described below may be combinedwith each other so long as they do not constitute a conflict with eachother.

Referring to FIG. 1 , FIG. 2 , and FIG. 3 , a calibration bracket 100provided in one embodiment of the present invention includes a base 10,a stand assembly 20 and a beam assembly 30. The stand assembly 20 isfixedly connected to the base 10. The beam assembly 30 includes a firstbeam portion 32, a second beam portion 34 and a connecting portion 36.The connecting portion 36 is mounted to the stand assembly 20. One endof the connecting portion 36 is pivotally connected to the first beamportion 32, and the other end of the connecting portion 36 is pivotallyconnected to the second beam portion 34. The first beam portion 32 andthe second beam portion 34 can respectively rotate toward each otherrelative to the connecting portion 36, so that the beam assembly 30 canbe folded. The first beam portion 32 and the second beam portion 34 canalso respectively rotate away from each other relative to the connectingportion 36, so that the beam assembly 30 can be unfolded.

The “mounting” includes fixed mounting such as welding mounting as wellas detachable mounting.

The beam assembly 30 may be used to mount a calibration element, forexample, a multi-line laser 200, a calibration target, a radarreflection or absorption device, and the like, to calibrate thevehicle-mounted driver assistant system.

In the calibration bracket 100 of the present embodiment, the first beamportion 32 and the second beam portion 34 can pivotally rotate relativeto the connecting portion 36, respectively, so that the beam assembly 30can be folded, thereby reducing a volume of the calibration bracket 100to facilitate shipment.

The first beam portion 32, the second beam portion 34 and the connectingportion 36 constitute a beam.

Optionally, the beam assembly is mounted to a top surface of a movablevertical rod. In this way, compared with the traditional calibrationbracket, a center of gravity of the beam assembly is closer to a centerof gravity of a vertical rod, which can improve the stability of thecalibration bracket, so that a base with a smaller area can be used.

Optionally, the first beam portion 32 and the second beam portion 34 canrotate toward each other relative to the connecting portion 36, forexample, which can be folded together downward, upward, forward, andbackward. Optionally, when the first beam portion 32 and the second beamportion 34 are folded downward, a length of the connecting portion 36can be relatively short, and the first beam portion 32 and the secondbeam portion 34 are in a drooping state. In this way, the beam assembly30 does not need to be removed from the stand assembly 20, and spaceoccupied by the calibration bracket 100 will be significantly reduced,which can be carried conveniently in vehicles. When the first beamportion 32 and the second beam portion 34 are folded upward, forward andbackward, a device for rotating the beam may be disposed, so that thefirst beam portion 32 and the second beam portion 34 are finally foldeddownward, or may be in a drooping state. Alternatively, the length ofthe connecting portion 36 can be made relatively long, so that the firstbeam portion 32 and the second beam portion 34 can be placed close tothe connecting portion 36 after being folded, and can be fixed onto theconnecting portion 36 by using a releasable fixing device. In the lattercase, in order to further reduce the space occupied by the calibrationbracket 100, the beam assembly 30 may be removed from the stand assembly20, carried to the place as needed, and then mounted onto the standassembly 20.

Those skilled in the art may understand that the manner in which thebeam assembly 30 is folded is not limited to the foregoing manner. Forexample, the beam may be folded into two ends, and there is noconnecting portion 36 at this time. The beam can also be folded intofour or more sections. However, three sections are exemplary, becausethis makes the middle section of the beam no fracture, so that only onefastening component can be used at the middle section to fix the beamonto the vertical rod stably.

The base 10 includes a base body 12, a roller 14, a height adjustmentmember 16 and a pull ring 18.

The base body 12 has a triangular claw shape and includes three clawsextending in three different directions. The base body 12 may be made ofa metal material.

The roller 14 is mounted to a bottom surface of the base body 12, andthere may be three rollers 14. Each of the rollers 14 is mounted to anend of a corresponding one of the claws to facilitate movement of thebase body 12. In the present embodiment, the roller 14 is anomni-directional moving roller, so that the base body 12 can move towardany direction.

The height adjustment member 16 is mounted to the base body 12 foradjusting a height of the base body 12. In the present embodiment, theheight adjustment member 16 is an adjustment knob, and there are threeheight adjustment members. There is at least one section of screw rodunder the knob, and the screw rod is mated with threads of a throughhole at the base to implement height adjustment. Each of the heightadjustment members 16 is mounted to a corresponding one of the claws andis close to a corresponding one of the rollers 14, and the three heightadjustment members 16 are distributed in a regular triangle.

The pull ring 18 can be mounted to an upper surface of one of the clawsto facilitate pulling of the calibration bracket 100.

It may be understood that, in some other embodiments, a shape of thebase body 12 may vary according to an actual demand, and is not limitedto a triangle claw shape. For example, the base body 12 may be arectangle or a circle. The number of rollers 14 and height adjustmentmembers 16 can be increased or decreased according to actual needs. Forexample, the triangular-claw-shaped base body 12 may be provided withtwo height adjustment members and mated with a foot with a fixed height,to adjust the angle of the base body 12.

Referring to FIG. 4 and FIG. 5 together, the stand assembly 20 mayinclude a fixed vertical rod 22, a movable vertical rod 24 and a drivingmechanism 26. The movable vertical rod 24 is sleeved in the fixedvertical rod 22, and can move along a length direction of the fixedvertical rod 22 relative to the fixed vertical rod 22. The drivingmechanism 26 is mounted to the fixed vertical rod 22 and configured todrive the movable vertical rod 24 to move along the length direction ofthe fixed vertical rod 22 relative to the fixed vertical rod 22. Byusing the connection manner in which the movable vertical rod 24 and thefixed vertical rod 22 are sleeved, the height of the stand assembly 20can be reduced to nearly half of the original height. The cross barassembly 30 is folded, so that the stand assembly 20 can be verysuitable for being placed in the trunk of the vehicle such as anautomobile for carrying.

It may be understood that the fixed vertical rod can also be used as aninner rod and the movable vertical rod as an outer rod as required. Thedriving mechanism 26 is mounted to the fixed vertical rod 22 andconfigured to drive the movable vertical rod 24 to move along a lengthdirection of the fixed vertical rod 22 relative to the fixed verticalrod 22.

Optionally, the fixed vertical rod 22 and the movable vertical rod 24are respectively square tubes. The movable vertical rod 24 is tightlysleeved in the fixed vertical rod 22, so that the movable vertical rod24 can move along the length direction of the fixed vertical rod 22relative to the fixed vertical rod 22, and the movable vertical rod 24can be prevented from moving toward other directions relative to thefixed vertical rod 22. This configuration is very important for thecalibration bracket 100 to be foldable. Because in the calibrationprocess, it is usually necessary to use the fixed relative positionrelationship between components of the calibration bracket 100. Forexample, it is possible to fix a laser on an outer surface of the fixedvertical rod 22. The laser is used to position the center axis of thevehicle, thereby determining the relative position between the targetcarried on the beam assembly 30 and the vehicle. Therefore, if therelative position of each component changes slightly, the calibrationaccuracy will be affected, or an additional fine-tuning mechanism willneed to be added to compensate. If the relative position between thecomponents changes greatly, it may cause the additional fine-tuningmechanism to fail. Therefore, in the folded mode, the relative movementbetween the movable vertical rod 24 and the fixed vertical rod 22 otherthan along the length direction, such as relative rotation, needs to beeliminated. A simple method is to make the movable vertical rod 24 andthe fixed vertical rod 22 as square tubes, which can ensure that onlyrelative movement along the length direction occurs between the two.

It may be understood that, in some other embodiments, the fixed verticalrod 22 and the movable vertical rod 24 may also be tubes of othershapes, for example, tubes with mutually matched polygonalcross-sections, so that the movable vertical rod 24 can move along thelength direction of the fixed vertical rod 22 relative to the fixedvertical rod 22, and the movable vertical rod 24 can be prevented frommoving toward other directions relative to the fixed vertical rod 22.The “mutually matched” herein does not necessarily require that thecross-sections of the fixed vertical rod 22 and the movable vertical rod24 need to be the same. For example, the cross-section of the fixedvertical rod 22 arranged outside may be hexagonal, and the cross-sectionof the movable vertical rod 24 arranged inside may be a quadrilateralconnected with the hexagon. As a result, the movable vertical rod 24 canonly move along the length direction of the fixed vertical rod 22relative to the fixed vertical rod 22. The cross-sections of the fixedvertical rod 22 and the movable vertical rod 24 can also be ellipticalcylindrical tubes that are mated with each other, and the ellipticalcross-section can also restrict the relative rotation between the two toa certain extent.

The fixed vertical rod 22 and the movable vertical rod 24 may also becylindrical tubes with a circular cross-section. In this case, the fixedvertical rod 22 can be prevented, by using a guide mechanism, fromrotating relative to the movable vertical rod 24, which is used to guidethe movable vertical rod 24 to move stably relative to the fixedvertical rod 22, or to add, on other components of the calibrationbracket 100, a mechanism for detecting and adjusting the movement of thefixed vertical rod 22 relative to the movable vertical rod 24 in otherdirections other than the length direction. A simple guide mechanism isa guide rail and a sliding block device matched with the guide rail. Theguide rail can be provided on one of the fixed vertical rod 22 and themovable vertical rod 24 on a contact surface of the fixed vertical rodand the movable vertical rod, and a slider device such as a bump, aplastic rubber strip, a roller, a ball, a gears, and the like on theother. In this case, the slider device will be restricted to move on theguide rail, which can also ensure that only the relative movement alongthe length direction occurs between the two vertical rods. The guiderail may be a groove, a linear protrusion, a rack, and the likeadditionally disposed on the tube wall of the vertical rod, or may be agroove formed by the tube wall itself of the vertical rod, a linearprotrusion, a groove formed between two linear protrusions, and thelike. That is, the vertical rod uses a special-shaped tube wall, and thetube wall itself has the groove, the linear protrusion, and the like,which can be used as a part of the guide rail. Similarly, the sliderdevice may be an additional component that is additionally disposed onthe tube wall of the vertical rod, or may be a protruding structureformed by the tube wall itself of the vertical rod, without the need todispose additional components on the tube wall of the vertical rod. Inaddition, a mechanism such as a rack that achieves transmission throughmeshing also has a guiding effect, which is also classified into thecategory of guide rails in this specification. The gear and racktransmission mechanism described in the following embodiments can alsoachieve the guiding effect. Optionally, the rack may be disposed in thegroove guide rail.

It may be understood that the positions at which the guide rail and theslider device are disposed can be interchanged, the guide rail may bedisposed on the movable vertical rod, the slider device may be disposedon the fixed vertical rod, and the positions for disposing the two canalso be exchanged.

It may be understood that the guide mechanism is not limited to thefixed vertical rod 22 and the movable vertical rod 24 with a circularcross-section. The fixed vertical rod 22 and the movable vertical rod 24of other cross-sectional shapes can also use a guide mechanism toenhance the guiding effect and obtain more stable or less frictionalrelative movement. For non-circular cross-sectional shapes, the guiderail may not be used, and only a linear motion device is used to obtainmore stable or less frictional relative movement. In this case, thenon-circular external vertical rod itself plays a guiding role.

The driving mechanism 26 includes a rack 260, a housing 261, a handle262 and a gear reduction assembly. The gear reduction assembly includesa first helical gear 263, a second helical gear 264, a firsttransmission gear 265 and a second transmission gear 266.

The rack 260 is fixedly mounted to the movable vertical rod 24 and isdisposed along a length direction of the movable vertical rod 24. Whenthe base 10 is placed on a horizontal plane, the fixed vertical rod 22,the movable vertical rod 24 and the rack 260 are all verticallydisposed.

The housing 261 is fixedly mounted to the fixed vertical rod 22.

The handle 262 is mounted to the housing 261 and can rotate around afirst rotation axis O1.

The gear reduction assembly can make the position of the movablevertical rod move more accurately and labor-saving, which facilitatesaccurate determining of a height of a calibration target. In the gearreduction assembly, the first helical gear 263 is located in the housing261 and is fixedly mounted to the handle 262. A rotation axis of thefirst helical gear 263 overlaps with a rotation axis of the handle 262,and the first helical gear 263 and the handle 262 can rotate togetherabout the first rotation axis O1.

The second helical gear 264 is mounted to an inner wall of the housing261 and can rotate around a second rotation axis O2. The first helicalgear 263 is engaged with the second helical gear 264, and a diameter ofthe first helical gear 263 is less than a diameter of the second helicalgear 264.

The first transmission gear 265 is fixedly mounted to the second helicalgear 264, the rotation axis of the first transmission gear 265 overlapswith the rotation axis of the second helical gear 264, and the firsttransmission gear 265 and the second helical gear 264 can rotate aroundthe second rotation axis O2 together.

The second transmission gear 266 is mounted to the inner wall of thehousing 261 and can rotate around a third rotation axis O3. The secondtransmission gear 266 is engaged with the first transmission gear 265and the rack 260, respectively. The second transmission gear 266 isprovided with a convex pillar 2662 for matching a ratchet wheel (notshown), so that the second transmission gear 266 is stopped at a presetposition. The first transmission gear 265 and the second transmissiongear 266 are both spur gears, and a diameter of the first transmissiongear 265 is less than a diameter of the second transmission gear 266.

The first rotation axis O1 is perpendicular to the second rotation axisO2 and the third rotation axis O3, and the first rotation axis O1 isperpendicular to the rack 260. The second rotation axis O2 and the thirdrotation axis O3 are arranged in parallel, and the second rotation axisO2 and the third rotation axis O3 are perpendicular to the rack 260.

When the handle 262 rotates around the first rotation axis O1, the firsthelical gear 263 is driven to rotate around the first rotation axis O1,the second helical gear 264 and the first transmission gear 265 rotatearound the second rotation axis O2, and the second transmission gear 266rotates around the third rotation axis O3. When the second transmissiongear 266 rotates around the third rotation axis O3, the rack 260 isdriven to rise or fall along the length direction of the movablevertical rod 24, so that the movable vertical rod 24 can rise or fallrelative to the fixed vertical rod 22.

In the present embodiment, the first helical gear 263 is engaged withthe second helical gear 264, the first transmission gear 265 and thesecond helical gear 264 can rotate together about the second rotationaxis O2, and the second transmission gear 266 is engaged with the firsttransmission gear 265 and the rack 260, respectively, so that themovable vertical rod 24 can be driven to move stably relative to thefixed vertical rod 22. In addition, the diameter of the first helicalgear 263 is less than the diameter of the second helical gear 264, andthe diameter of the first transmission gear 265 is less than thediameter of the second transmission gear 266, so that the movablevertical rod 24 can be driven, through a relatively small force, to moverelative to the fixed vertical rod 22.

It may be understood that in some other embodiments, the first helicalgear 263 and the second helical gear 264 can be omitted. The firsttransmission gear 265 is fixedly mounted to the handle 262, and thehandle 262 can rotate around the second rotation axis O2, therebydriving the first transmission gear 265 to rotate around the secondrotation axis O2.

It may be understood that in some other embodiments, the first helicalgear 263, the second helical gear 264 and the first transmission gear265 can be omitted. The second transmission gear 266 is fixedly mountedto the handle 262, and the handle 262 can rotate around the thirdrotation axis O3, thereby driving the second transmission gear 266 torotate around the third rotation axis O3.

Referring to FIG. 6 , in some embodiments, the first helical gear 263,the second helical gear 264 and the first transmission gear 265 can bereplaced with a worm mechanism, and the worm mechanism includes a worm263 a and a worm gear 265 a.

One end of the worm 263 a is fixedly mounted to the handle 262, therotation axis of the worm 263 a overlaps with the rotation axis of thehandle 262, and the worm 263 a and the handle 262 can rotate togetherabout the first rotation axis O1.

The worm 263 a is cylindrical, and an outer surface of the worm has atooth portion 264 a engaged with the worm gear 265 a.

The worm gear 265 a is fixedly mounted to the second transmission gear266, a rotation axis of the worm gear 265 a overlaps with a rotationaxis of the second transmission gear 266, and the worm gear 265 a andthe second transmission gear 266 can rotate together around the secondrotation axis O2. A diameter of the worm gear 265 a is less than thediameter of the second transmission gear 266, so that the movablevertical rod 24 can be driven, through a relatively small force, to moverelative to the fixed vertical rod 22. The first rotation axis O1 isperpendicular to the second rotation axis O2, and the second rotationaxis O2 is perpendicular to the rack 260.

When the movable vertical rod 24 is moved to a desired position relativeto the fixed vertical rod 22, the movable vertical rod 24 can be fixedat the desired position via the self-locking function of the wormmechanism.

It may be understood that, in some other embodiments, the handle 262 maybe replaced with a motor.

It may be understood that, in some other embodiments, in addition to thegear box, the driving mechanism 26 may be other driving mechanisms, suchas a screw drive, a timing belt, and the like, as long as the movablevertical rod 24 can be driven to move relative to the fixed vertical rod22.

In some embodiments, the movable vertical rod 24 is provided with alimiting member 242, the limiting member 242 is located in the fixedvertical rod 22. The inner wall of the fixed vertical rod 22 is providedwith a flange, and the flange is close to the top of the fixed verticalrod 22. When the movable vertical rod 24 moves relative to the fixedvertical rod 22 until the limiting member 242 abuts against the flange,the movable vertical rod 24 stops moving, which can prevent the movablevertical rod 24 from being separated from the fixed vertical rod 22. Inthe present embodiment, the limiting member 242 is a lantern ring, whichis sleeved on an outer wall of the movable vertical rod 24.

Referring to FIG. 7 and FIG. 8 , in some embodiments, the drivingmechanism 26 is omitted, and the stand assembly 20 further includes afastening mechanism 27 and an elastomer 28.

The fastening mechanism 27 may be mounted to one end of the fixedvertical rod 22 and configured to fix the movable vertical rod 24 to thefixed vertical rod 22. The fastening mechanism 27 includes a fasteningring 272 and a bolt 274. The fastening ring 272 is sleeved on the fixedvertical rod 22 and can be formed by bending a metal strip. The bolt 274is mounted to two ends of the fastening ring 272.

The elastomer 28 is located in the fixed vertical rod 22 and the movablevertical rod 24, and the elastomer 28 is compressed between the bottomof the fixed vertical rod 22 and the movable vertical rod 24. Accordingto requirements, the elastomer 28 can be connected to the movablevertical rod 24 at a position of the bottom, top or middle of themovable vertical rod 24. When the movable vertical rod moves to thebottom closest to the fixed vertical rod, the elastomer is in acompressed state. In the present embodiment, the elastomer 28 is acompression spring. It may be understood that, in some otherembodiments, the elastomer 28 may be other elastic elements such as anelastic piece, a pneumatic rod, a hydraulic rod, and the like.

When the movable vertical rod 24 needs to be raised relative to thefixed vertical rod 22, the bolt 274 is rotated, so that the fasteningring 272 loosens the fixed vertical rod 22, and exerts upward force onthe movable vertical rod 24. Therefore, the movable vertical rod 24 canrise along the length direction of the fixed vertical rod 22, and theelastic force of the elastomer 28 can be used to reduce the externalforce applied to the movable vertical rod 24, for example, the externalforce applied by the operator. When the required position is reached,the bolt 274 is rotated to fasten the fixed vertical rod 22, so that themovable vertical rod 24 is fixed at the required position. When themovable vertical rod 24 needs to be lowered relative to the fixedvertical rod 22, the bolt 274 is rotated, so that the fastening ring 272loosens the fixed vertical rod 22. Under the gravity of the movablevertical rod 24 and the beam assembly 30, the movable vertical rod 24can fall along the length direction of the fixed vertical rod 22, andthe elastic force of the elastomer 28 can be used to reduce the fallingspeed of the movable vertical rod 24 to prevent the movable vertical rod24 from damage caused by colliding with the fixed vertical rod 24 due tofalling too fast.

It may be understood that, in some other embodiments, the fasteningmechanism 27 may also have other structures, as long as the movablevertical rod 24 can be fixed at a desired position. For example, thefastening mechanism 27 may be a screw, which passes through the fixingvertical rod 22 and is in screw-thread fit with the fixed vertical rod22. When the movable vertical rod 24 moves to a desired positionrelative to the fixed vertical rod 22, the screw is rotated to abutagainst the movable vertical rod 24, so that the movable vertical rod 24can be fixed at the required position. The screw is rotated to beseparated from the movable vertical rod 24, and the movable vertical rod24 can move along the length direction of the fixed vertical rod 22relative to the fixed vertical rod 22.

Referring to FIG. 9 , FIG. 10 and FIG. 11 , the beam assembly 30includes a first supporting rod 31, the first beam portion 32, a secondsupporting rod 33, the second beam portion 34, a mounting seat 35, theconnecting portion 36, an adjustment mechanism 37 and a joint mechanism39. The function of the first supporting rod 31 and the secondsupporting rod 33 is to lift the target to prevent falling, especiallywhen the target area is relatively large and the weight is relativelylarge.

One end of the first supporting rod 31 can be pivotally connected to thefirst beam portion 32 through a hinge mechanism, and the like, and thefirst supporting rod 31 can rotate relative to the first beam portion 32to be unfolded to be perpendicular to the first beam portion 32 andengaged with and parallel to the first beam portion 32.

The first supporting rod 31 includes a first supporting rod body 310 anda first supporting member 312. One end of the first supporting rod body310 is hinged to the first beam portion 32, and the first supportingmember 312 is mounted at the other end of the first supporting rod body310. A side wall of the first supporting rod body 310 is provided with afirst slot (not shown).

Similarly, one end of the second supporting rod 33 can be pivotallyconnected to the second beam portion 34 through a hinge mechanism, andthe like, and the second supporting rod 33 can rotate relative to thesecond beam portion 34 to be unfolded to be perpendicular to the secondbeam portion 34 and engaged with and parallel to the second beam portion34. The second supporting rod 33 includes a second supporting rod body330 and a second supporting member 332. One end of the second supportingrod body 330 is hinged to the second beam portion 34, and the secondsupporting member 332 is mounted at the other end of the secondsupporting rod body 330. A side wall of the second supporting rod body330 is provided with a second slot 3300. The first supporting member 312and the second supporting member 332 extend in the same direction. Whenthe first supporting rod 31 is unfolded to be perpendicular to the firstbeam portion 32, and the second supporting rod 33 is unfolded to beperpendicular to the second beam portion 34, the first slot and thesecond slot 3300 are arranged oppositely, and the first supportingmember 312 and the second supporting member 332 can be used to jointlysupport a calibration element, such as a pattern plate.

The first beam portion 32 is provided with a first fixture block 320 anda first guide rail 322. The first fixture block 320 and the firstsupporting rod 31 are both connected to the same side of the first beamportion 32. When the first supporting rod 31 is rotated to be parallelto the first beam portion 32, the first fixture block 320 is engagedinto the first slot, and the first supporting rod 31 is snapped into thefirst beam portion 32. The first guide rail 322 is disposed on the otherside of the first beam portion 32 and parallel to the first beam portion32. The first guide rail 322 is configured to mount a widget formounting the calibration element, for example, mounting a calibrationtarget, a reflector, a laser, and the like. The widget can slide alongthe first guide rail 322.

Similarly, the second beam portion 34 is provided with a second fixtureblock 340 and a second guide rail 342. The second fixture block 340 andthe second supporting rod 33 are both connected to the same side of thesecond beam portion 34. When the second supporting rod 33 is rotated tobe parallel to the second beam portion 34, the second fixture block 340is engaged into the second slot 3300, and the second supporting rod 33is snapped into the second beam portion 34. The second guide rail 342 isdisposed on the other side of the second beam portion 34 and parallel tothe second beam portion 34. The second guide rail 342 is configured tomount a widget for mounting the calibration element, for example,mounting a reflector, and the like. The widget can slide along thesecond guide rail 342. The first guide rail 322 and the second guiderail 342 are disposed symmetrically relative to the connecting portion36, and the first beam portion 32 and the second beam portion 34 arealso disposed symmetrically relative to the connecting portion 36. Whenthe base 10 is placed on a horizontal plane, the first guide rail 322,the second guide rail 342, the first beam portion 32 and the second beamportion 34 are all horizontally disposed.

It may be understood that, in some other embodiments, the positions ofthe first fixture block 320 and the first slot can be interchanged, thatis, the first fixture block 320 is mounted to the first supporting rodbody 310, and the first slot is provided on the first beam portion 32.Similarly, the positions of the second fixture block 340 and the secondslot 3300 can also be interchanged, that is, the second fixture block340 is mounted to the second supporting rod body 330, and the secondslot 3300 is provided on the second beam portion 34. Optionally, thefirst slot and the second slot 3300 are recessed in the correspondingbeam portion.

It may be understood that, in some other embodiments, the first guiderail 322 and the second guide rail 342 may be disposed on other surfacesof the beam, such as the top surface. In some other embodiments, thefirst guide rail 322 and the second guide rail 342 do not need to bedisposed, and the calibration element may be directly hung on the beamby using a hook or the like. The first guide rail 322 and the secondguide rail 342 can also have other forms, which are not necessarilyshown in the figure. For example, the guide rail can be one or moregroove lines arranged on the top surface of the beam, and the outer wallof the beam can be used to form the groove line without mountingadditional guide rails.

It may be understood that the number of supporting rods is not limitedby the foregoing embodiment. For example, there may be only onesupporting rod that is disposed at the approximate center of theconnecting portion 36. In this case, the target located at theapproximate center of the beam assembly 30 can also be lifted well. Whenthe target used for calibration is located at other positions, thesupporting rod can also be disposed at the corresponding position forlifting. There may be more than two supporting rods. In addition, thesupporting rod can also be disposed on a rail, and the rail is disposedon a side surface or a bottom surface of the beam assembly 30, so thatthe supporting rod can move along the assembled beam assembly 30, so asto lift, at a suitable position, the targets that may be at differentpositions.

It may be understood that when the guide rail is used to make thesupporting rod movable, the supporting rod can also be snapped onto thebeam assembly 30 by using a fixture block and a slot.

The connecting portion 36 of the beam is sleeved in the mounting seat35, and a first surface 360 of the connecting portion 36 is recessedwith positioning holes 3604. There are preferably two positioning holes3604, which are disposed along the length direction of the connectingportion 36.

Referring to FIG. 12 , the connecting portion 36 is provided with afixing groove 3620, a fixing surface 3624 is disposed in the fixinggroove 3620, and the fixing groove 3620 is used in conjunction with thefixing rod 354 in FIG. 13 to fix the beam assembly onto the mountingseat 35. Optionally, the fixing groove 3620 is provided so that thefixing surface 3624 and the bottom surface of the mounting seat 35 areat a certain angle. The advantages of this arrangement are described incombination with the fixing rod in FIG. 13 . For example, the fixinggroove 3620 may be disposed between a second surface 362 and a topsurface of the beam. The second surface 362 is arranged parallel to thefirst surface 360, and there is an included angle between the fixingsurface 3624 and the first surface 360 and the second surface 362. Forexample, the fixing surface 3624 is disposed at 45 degrees with thefirst surface 360 and the second surface 362.

In the present embodiment, the first beam portion 32, the second beamportion 34 and the connecting portion 36 are all square tubes, which canreduce the weight of the calibration bracket 100 and make the connectingportion 36 easy to be firmly sleeved in the adjustment mechanism 38. Itmay be understood that, in some other embodiments, the first beamportion 32, the second beam portion 34 and the connecting portion 36 mayalso be tubes of other shapes, special-shaped materials, rods, or thelike, which may be polygonal or circular tubes or rods, for example.When the beam is a tube of other shapes, the fixing groove 3620 may bedisposed at a position at which a certain angle is formed between thefixing surface 3624 and the bottom surface of the mounting seat 35.

Referring to FIG. 13 and FIG. 14 , the mounting seat 35 is sleeved inthe connecting portion 36. The mounting seat 35 includes a holder 352, afixing rod 354 and a mounting housing 356.

Optionally, the mounting seat 35 may be disposed on the adjustmentmechanism 37, so that the mounting seat 35 can rotate around theadjustment rotation axis L relative to the stand assembly 20 under theadjustment of the adjustment mechanism 37, to adjust the horizontalangle of the mounting seat 35 and the beam assembly 30. Preferably, theadjustment mechanism 37 and the mounting seat are disposed up and down,so as to facilitate the removal and mounting of the beam from abovewhile implementing adjustment of the horizontal angle.

The adjustment rotation axis L is disposed parallel to the fixedvertical rod 22 and the movable vertical rod 24, that is, when thecalibration bracket 100 is placed on a horizontal plane, the adjustmentrotation axis L is disposed vertically. The mounting seat 35 is providedwith a notch 350 for conveniently putting the connecting portion 36 intothe mounting seat 35 or removing the connecting portion 36 from themounting seat 35.

The holder 352 is generally hook-shaped to facilitate holding of theconnecting portion 36. One end of the holder 352 is fixedly connected tothe mounting housing 356, for example, mounted on the upper surface orside surface of the mounting housing 356, and the other end surroundsand grasps the connecting portion 36 of the beam assembly 20, leavingthe notch 350. For example, the holder 352 may have the shape shown inFIG. 13 , or may have other shapes, such as a circular hook shape, ahook shape of other polygons, a hook shape combined with a circular ringand a polygon, as long as the connecting portion 36 can be stablycontrolled. The “substantially hook-shaped” herein means that the holder352 can extend by a certain length from a certain angle, therebysupporting and holding the connecting portion 36.

The holder 352 and the mounting housing 356 enclose a mounting channelfor accommodating the connecting portion 36. The mounting channel is incommunication with the notch 350. Two positioning columns 3524 areprovided on the inner surface of the holder 352, which are located inthe mounting channel for being inserted into the two positioning holes3604 (see FIG. 8 ), to facilitate positioning of the connecting portion36 in the mounting channel. The function of the positioning hole is tofurther reduce any displacement of the beam assembly 20 relative to themounting seat 35 in the horizontal direction during calibration. Thepositioning column 3524 may also be disposed on the upper surface of themounting housing 356 or on both the upper surface of the mountinghousing 356 and the inner surface of the holder 352. The “positioningcolumn” herein includes round, square, and elongated positioningcolumns, and the “positioning hole” includes round, square, andelongated positioning holes. When the positioning column and thepositioning holes are generally point-shaped, there are preferably atleast two positioning columns 3524 along the length direction of theconnecting portion 36, to ensure that the connecting portion 36 does notmove along the length direction. When the positioning column and thepositioning hole are roughly elongated, only one pair of positioningcolumn and one positioning hole can be used. It may be understood that,in some other embodiments, positions of the positioning hole 3604 andthe positioning column 3524 can be interchanged, that is, thepositioning hole 3604 is disposed on the holder 352 and in communicationwith the mounting channel, and the positioning column 3524 is disposedon the first surface 360 (see FIG. 8 ).

Optionally, the fixing rod 354 is disposed on the holder 352, whichincludes a knob and at least one section of screw rod and is mated withthreads of the holder 352. When the connecting portion 36 is sleeved onthe mounting seat 35, the central axis of the fixing rod 354 isperpendicular to the fixing surface 3624 at the beam connecting portion36. By rotating the fixing rod 354, the fixing rod 354 can abut againstthe fixing surface 3624, and the connecting portion 36 of the beamassembly can be fixed to the mounting seat 35. Alternatively, byrotating the fixing rod 354, the fixing rod 354 can be separated fromthe fixing surface 3624, and the connecting portion 36 can be removedfrom the mounting seat 35 through the notch 350.

Optionally, the fixing surface 3624 and the bottom surface (that is, ahorizontal plane) of the mounting seat 35 are at a certain angle, andthe fixing rod 354 and the bottom surface of the mounting seat 35 are ata certain angle, the angle being greater than 0 degree and less than 90degrees. Optionally, the angle is substantially 45 degrees. With thisarrangement, only one fixing rod 354 can be used to apply, to theconnecting portion 36, a pressing force toward the bottom surface and aside surface of the mounting seat. The side surface is a side oppositeto a direction in which the fixing rod 354 extends, thereby fixing theconnecting portion 36 with high stability by using a fixing seat, sothat the beam assembly can be easily disassembled and assembled.

It may be understood that the mounting seat 35 may have otherstructures, for example, a notch may not necessarily be maintained.After the connecting portion 36 is placed in the mounting seat 35, abaffle or the like can be used to block the notch. The connectingportion 36 can also be mounted in other ways. For example, the mountingseat 35 may be a complete ring structure without a notch for placing thebeam. In this case, the beam may be assembled first, then the mountingseat 35 can be inserted, and then the fixing rod 354 is used to tightenand fix the beam.

It may be understood that the bottom surface or side surface of themounting seat 35 pressed by the connecting portion 36 may be arc-shapedor other irregular shapes. In this case, the fixing rod 354 may also beused to press the connecting portion 36 on these surfaces. There may beline contact between the fixing rod and these surfaces instead ofsurface contact, which will not affect the compression effect.

Optionally, when the mounting seat 35 includes a notch 350, the surfaceof the mounting seat 35 facing away from the notch 350 may also be usedto mount a calibration element, for example, a multi-line laser 200 (seeFIG. 1 ).

The mounting housing 356 is generally a cube with an opening on oneside. The adjustment mechanism 37 is disposed in the opening of themounting housing 356. The mounting housing 356 is provided with athreaded hole 3562. The adjustment mechanism 37 includes a supportingshaft 371, a first elastic member 372, a rotating member 373, a bearingseat 374, a base 375 and an adjusting rod 376. The adjustment mechanism37 is configured to adjust the angle of the beam assembly 20 in thehorizontal direction (that is, a yaw angle).

The supporting shaft 371 is accommodated in the mounting housing 356 andfixedly mounted to the inner wall of the mounting housing 356. A centralaxis of the supporting shaft 371 overlaps with the adjustment rotationaxis L.

One end of the first elastic member 372 is fixed to the mounting column3560, and the other end of the first elastic member 372 is fixed to therotating member 373. In the present embodiment, the first elastic member372 is a spring.

The rotating member 373 is substantially a cube, one end of which isprovided with a protrusion 3732, and the protrusion 3732 and the firstelastic member 372 are respectively located on two opposite sides of therotating member 373. The rotating member 373 is sleeved on the bearingseat 374.

The bearing seat 374 is fixedly mounted to a surface of the base 375,and a central axis of the bearing seat 374 overlaps with the adjustmentrotation axis L. The rotating member 373 is fixedly mounted to the base375 and sleeved on the bearing seat 374. One end of the supporting shaft371 is inserted into the bearing seat 374, so that the supporting shaft371 and the mounting housing 356 can rotate together around theadjustment rotation axis L relative to the rotating member 373, thebearing seat 374 and the base 375.

The base 375 is mounted to the movable vertical rod 24, and the movablevertical rod 24 can drive the base 375 to rise or fall. In the presentembodiment, the base 375 is a cube and covers the opening of themounting housing 356. The supporting shaft 371, the first elastic member372 and the rotating member 373 are all accommodated in a cavity formedby the mounting housing 356 and the base 375.

The “cube” in this specification includes a thin plate shape.

The adjusting rod 376 is mounted in the threaded hole 3562, and byrotating the adjusting rod 376, the adjusting rod 376 abuts against theprotrusion 3732, and pushes the mounting seat 35 to rotate about theadjustment rotation axis L relative to the rotating member 373 and thebase 375, thereby adjusting the horizontal angle of the mounting seat 35and the connecting portion 36, so that the first elastic member 372 isstretched. The adjusting rod 376 is rotated in the opposite direction,and the mounting seat 35 can be pulled, by using the first elasticmember 372, to rotate and reset around the adjustment rotation axis Lrelative to the rotating member 373 and the base 375.

It may be understood that, in some other embodiments, the base 375 maybe omitted, and the rotating member 373 and the bearing seat 374 may befixedly mounted to the top surface of the movable vertical rod 24directly.

It may be understood that the foregoing adjustment mechanism 37 may beselectively used. When the adjustment mechanism 37 is removed, themounting housing 356 of the mounting seat 35 can be removed, and theholder 352 is mounted onto the top surface of the movable vertical rod24 or other additional mounting surfaces. It should be understood thatthe holder 352 may also extend to form a bottom surface and surround thelower surface of the connecting portion 36 of the beam assembly 30, thatis, the holder 352 may have a bottom surface mounted onto the mountinghousing 356.

Referring to FIG. 10 again, there are two joint mechanisms 39. One ofthe joint mechanisms 39 is connected between the first beam portion 32and the connecting portion 36, and the other of the joint mechanisms 39is connected between the second beam portion 34 and the connectingportion 36. In some embodiments, the joint mechanism 39 is fixed in thewall tubes of the first beam portion 32, the second beam portion 34 andthe connecting portion 36. In some embodiments, the joint mechanism 39is fixed outside the wall tubes of the first beam portion 32, the secondbeam portion 34 and the connecting portion 36, and is connected tocross-sections of the wall tubes of the first beam portion 32, thesecond beam portion 34 and the connecting portion 36 by snapping,screwing, bonding, and the like.

Referring to FIG. 15 , FIG. 16 and FIG. 17 together, a first embodimentof a structure of a joint mechanism 39 is shown. The joint mechanism 39includes a first fixing member 391, a second fixing member 396, a firstrotating shaft 397, a fastening member 392, a second rotating shaft 393,a second elastic member 394 and a screwing mechanism 395.

The first fixing member 391 and the second fixing member 396 arepivotally connected through the first rotating shaft 397. The firstfixing member 391 is substantially a cube, one end of which is hinged toone end of the second fixing member 396. The first fixing member 391 isprovided with a first through hole 3910.

The fastening member 392 is accommodated in the first through hole 3910,the second rotating shaft 393 passes through the middle of the fasteningmember 392, and two ends of the second rotating shaft 393 arerespectively mounted to a side wall of the first fixing member 391. Thefastening member 392 may rotate around the second rotating shaft 393, ahook portion 3922 extends from one end of the fastening member 392, oneend of the second elastic member 394 abuts against the other end of thefastening member 392, and the other end of the second elastic member 394abuts against the inner wall of the first fixing member 391. The secondelastic member 394 is a compression spring for restoring elasticdeformation to push the fastening member 392 to rotate around the secondrotating shaft 393.

The screwing mechanism 395 includes a knob and at least one section ofscrew rod. One end of the screwing mechanism 395 passes through thefirst fixing member 391 from the outside of the first fixing member 391,and abuts against the fastening member 392. The screwing mechanism 395and the second elastic member 394 are located on the same side of thecentral axis of the second rotating shaft 393, and the hook portion 3922is located on the other side of the central axis of the second rotatingshaft 393.

The second fixing member 396 is also substantially a cube and providedwith a second through hole 3960. An inner wall of the second throughhole 3960 is provided with a locking protrusion 3962. The first fixingmember 391 is fixed to the inside of the connecting portion 36, and thesecond fixing member 396 is fixed to the inside of the first beamportion 32 or the second beam portion 34, so that the first beam portion32 or the second beam portion 34 can be engaged with the connectingportion 36.

When the first fixing member 391 and the second fixing member 396 arefastened, the first fixing member 391 is in contact with the secondfixing member 396, and the first through hole 3910 is in communicationwith the second through hole 3960. Pushed by the second elastic member394, the hook portion 3922 is fastened to the locking protrusion 3962,and the screwing mechanism 395 is rotated, so that the screwingmechanism 395 presses the fastening member 392, and the hook portion3922 is further fastened to the locking protrusion 3962, so that thefirst beam portion 32 or the second beam portion 34 is stably unfoldedrelative to the connecting portion 36.

The screwing mechanism 395 is rotated to be disengaged from thefastening member 392, so that the first fixing member 391 rotatesrelative to the second fixing member 396, and the hook portion 3922 isseparated from the locking protrusion 3962. The first fixing member 391is separated from the second fixing member 396, so that the first beamportion 32 or the second beam portion 34 can rotate relative to theconnecting portion 36, and the beam assembly 30 is folded.

In the present embodiment, pushed by the second elastic member 394, thehook portion 3922 can be easily fastened to the locking protrusion 3962,so that the hook portion 3922 and the locking protrusion 3962 arefastened to each other in advance, and then the screwing mechanism 395presses the fastening member 392, so that the hook portion 3922 isfurther fastened to the locking protrusion 3962.

It may be understood that, in some other embodiments, positions of thefirst fixing member 391 and the second fixing member 396 can beinterchanged, that is, the first fixing member 391 is fixed to theinside of the first beam portion 32 or the second beam portion 34, andthe second fixing member 396 is fixed to inside of the connectingportion 36.

It may be understood that the first fixing member 391 and the secondfixing member 396 may also be integrally formed with inner walls of thefirst beam portion 32, the second beam portion 34 or the connectingportion 36, that is, the first fixing member 391 and the second fixingmember 396 may be a part of the inner walls of the first beam portion32, the second beam portion 34 or the connecting portion 36. The firstfixing member 391 and the second fixing member 396 may not be connectedby using a first rotating shaft or are not connected. However, the firstbeam portion 32 or the second beam portion 34 and the outer wall of theconnecting portion 36 are connected by using an additional rotatingshaft, which can also implement the pivotable connection between thefirst beam portion 32 or the second beam portion 34 and the connectingportion 36.

It may be understood that relative positions between the second elasticmember 394 and the screwing mechanism 395 and the second rotating shaft393 may be changed, that is, the second elastic member 394 may be closerto the second rotating shaft 393 than the screwing mechanism 395, aslong as the fastening member 392 can be fastened to the lockingprotrusion 3962.

Referring to FIG. 18 and FIG. 19 together, a second embodiment of astructure of a joint mechanism 39 is shown. The joint mechanism 39 aprovided by the second embodiment is basically the same as the jointmechanism 39 in the foregoing embodiment. A difference is that one endof the fastening member 392 a is provided with a hook portion 3922 a anda bump 3924 a. Two hook portions 3922 a are located on two oppositesides of the bump 3924 a, and the inner wall of the second through hole3960 is provided with a locking protrusion 3962 a. There are two lockingprotrusions 3962 a, and a position of each of the locking protrusions3962 a corresponds to a position of a corresponding one of the hookportions 3922 a. The knob 395 is replaced with a button 395 a, and thebutton 395 a is mounted to the second fixing member 396. The secondelastic member 394 is a compression spring compressed between the firstfixing member 391 and the fastening member 392 a.

When the first fixing member 391 and the second fixing member 396 arefastened, the first fixing member 391 is in contact with the secondfixing member 396, and the first through hole 3910 is in communicationwith the second through hole 3960. The second elastic member 394 ispressed against the fastening member 392 a, so that the two hookportions 3922 a are respectively fastened to the two locking protrusions3962 a. The first fixing member 391 and the second fixing member 396 aremutually fastened to each other, so that the first beam portion 32 orthe second beam portion 34 is unfolded relative to the connectingportion 36.

When the button 395 a is pressed, and the button 395 a pushes the bump3924 a to push the fastening member 392 a to rotate around the secondrotating shaft 393, the hook portion 3922 a is separated from thelocking protrusion 3962 a, and the second elastic member 394 is furthercompressed. In this case, the first fixing member 391 can rotaterelative to the second fixing member 396, so that the first fixingmember 391 is separated from the second fixing member 396, and the firstbeam portion 32 or the second beam portion 34 can rotate relative to theconnecting portion 36, to fold the beam assembly 30. The button 395 a isloosened to make the button 395 a far away from the fastening member 392a, and the second elastic member 394 recovers elastic deformation topush the fastening member 392 a to rotate around the second rotatingshaft 393, so that the hook portion 3922 a is fastened to the lockingprotrusion 3962 a.

Referring to FIG. 20 , in order to increase the engagement strength ofthe first beam portion 32 and the second beam portion 34 with theconnecting portion 36 respectively, so that the first beam portion 32and the second beam portion 34 can be mounted with a calibration elementwith a more weight, the calibration bracket 100 may further include afastening structure 50. One fastening structure 50 is connected betweenthe first beam portion 32 and the connecting portion 36, and the otherfastening structure 50 is connected between the second beam portion 34and the connecting portion 36.

Each of the fastening structures 50 includes a first fastener 52 and asecond fastener 54. The connecting portion 36 is provided with a firstfastener 52, one end of the first fastener 52 is hinged to theconnecting portion 36, and one end of the first fastener 52 hinged tothe connecting portion 36 is provided with a pulling portion 522. Theother end of the first fastener 52 is provided with a hook rod 524, andthe first beam portion 32 or the second beam portion 34 is provided witha second fastener 54. The second fastener 54 is provided with afastening portion 544. A hinge joint of the first beam portion 32 or thesecond beam portion 34 and the connecting portion 36 is located on oneside of the connecting portion 36, and the first fastener 52 and thesecond fastener 54 are located on the other side of the connectingportion 36. When the first beam portion 32 and the second beam portion34 are unfolded relative to the connecting portion 36, the first beamportion 32 and the second beam portion 34 are respectively in contactwith the connecting portion 36, and the hook rod 524 is fastened to thefastening portion 544. By pulling the pulling portion 522, the hook rod524 is separated from the fastening portion 544, and the first fastener52 and the second fastener 54 may be separated, so that the first beamportion 32 or the second beam portion 34 can be folded relative to theconnecting portion 36.

It may be understood that, in some other embodiments, positions of thefirst fastener 52 and the second fastener 54 can be interchanged, thatis, the first fastener 52 is disposed on the first beam portion 32 orthe second beam portion 34, and the second fastener 54 is disposed onthe connecting portion 36. In some embodiments, the first fastener 52and the second fastener 54 can be used in conjunction with the jointmechanism 39. That is, in this case, the joint mechanism 39 is disposedin inner walls of the first beam portion 32, the second beam portion 34and the connecting portion 36. In some embodiments, the first fastener52 and the second fastener 54 can be used alone. That is, in this case,the joint mechanism 39 is not disposed in inner walls of the first beamportion 32, the second beam portion 34 and the connecting portion 36.

Referring to FIG. 21 and FIG. 22 together, another embodiment of thepresent invention also provides a calibration system 600, including acalibration element and the calibration bracket 100 provided in theforegoing embodiments. The calibration element can be mounted to thecalibration bracket 100. For example, the calibration element is areflector 300 and a distance measurement device 400 (see FIG. 21 ). Thereflector 300 may be mounted on a first guide rail 322 or a second guiderail 342 via a slider. The slider is mounted to the first guide rail 322or the second guide rail 342, and can slide along the first guide rail322 or the second guide rail 342 together with the reflector 300, andthe distance measurement device 400 is fixedly mounted to the beamassembly 30. The reflector 300 may also be a target 300, and two targetsare mounted on the first guide rail 322 and the second guide rail 342through the slider. The reflector or target 300 may further be directlymounted on the beam assembly 30 by using a hook, or the like. In thiscase, the first guide rail 322 and the second guide rail 342 may beremoved.

The foregoing distance measurement device 400 is used to measure theheight of the beam assembly 30 from the ground, which is preferablydisplayed on a liquid crystal display screen of the distance measurementdevice 400. In one embodiment, the distance measurement device 400 is alaser rangefinder. A through hole 120 is disposed on the base 10 formaking the laser of the laser rangefinder 400 strike the ground, tomeasure the height of the beam assembly 30 from the ground.

In another example, the calibration element is a pattern plate 500 (seeFIG. 22 ), and the first supporting member 312 and the second supportingmember 332 jointly lift the pattern plate 500 to prevent falling. Inaddition, a first fixing block 510 may be mounted on the first guiderail 322 and may slide along the first guide rail 322. A second fixingblock 520 is mounted on the second guide rail 342 and may slide alongthe second guide rail 342. The first fixing block 510 and the secondfixing block 520 are respectively located on two opposite sides of thepattern plate 500, and collaboratively clamp the pattern plate 500.

In an optional embodiment, the first fixing block 510 and the secondfixing block 520 are sliders to which the reflector 300 is mounted. Aslot is disposed on the opposite side of the slider to clamp the patternplate 500, so that a fixing block can be formed. It may be understoodthat the first fixing block 510 and the second fixing block 520 may alsobe magnetic blocks, which can attract the pattern plate 500 from behindthrough magnetic adsorption, to enhance the firmness of the patternplate 500 mounted on the beam assembly 30.

Finally, it should be noted that: The foregoing embodiments are merelyintended for describing the technical solutions of the presentinvention, but not for limiting the present invention. Under thethinking of the present invention, combinations may also be made betweenthe technical characteristics in the above embodiments or in differentembodiments, the steps may be implemented in any order, and there aremany other variations in different aspects of the invention as describedabove, which are not provided in detail for simplicity. Although thepresent invention is described in detail with reference to the foregoingembodiments, persons of ordinary skill in the art should understand thatthey may still make modifications to the technical solutions describedin the foregoing embodiments or make equivalent replacements to sometechnical features thereof, without departing from the scope of thetechnical solutions of the embodiments of the present invention.

What is claimed is:
 1. A calibration bracket, comprising: a base; astand assembly fixedly connected to the base, the stand assemblycomprising: a fixed vertical rod, the fixed vertical rod being fixedlymounted to the base; a movable vertical rod, the movable vertical rodbeing arranged in the fixed vertical rod and being capable of movingonly along a length direction of the fixed vertical rod relative to thefixed vertical rod; and a driving mechanism mounted to the fixedvertical rod and configured to drive the movable vertical rod to moveonly along a length direction of the fixed vertical rod relative to thefixed vertical rod; and a beam assembly mounted to the stand assemblyand being configured to mount a calibration element, the calibrationelement being configured to calibrate a vehicle-mounted driver assistantsystem, wherein the beam assembly comprises: a first beam portion, asecond beam portion and a connecting portion, one end of the connectingportion being pivotally connected to the first beam portion, the otherend of the connecting portion being pivotally connected to the secondbeam portion; wherein the connecting portion is mounted to top surfaceof the movable vertical rod.
 2. The calibration bracket according toclaim 1, wherein the stand assembly further comprises a guide mechanism,the guide mechanism being configured to guide the movable vertical rodto move only along the length direction of the fixed vertical rodrelative to the fixed vertical rod, and the guide mechanism comprising:a grooved formed on a tube wall of the fixed vertical rod; and a linearprotrusion formed on a tube wall of the movable vertical rod, the linearprotrusion being engaged with the groove.
 3. The calibration bracketaccording to claim 1, wherein the first beam portion and the second beamportion are able to rotate toward each other relative to the connectingportion and able to rotate downward relative to the connecting portion.4. The calibration bracket according to claim 1, wherein the first beamportion comprises a first guide rail and the second beam portioncomprises a second guide rail, the first guide rail and the second guiderail being disposed symmetrically relative to the connecting portion. 5.The calibration bracket according to claim 1, wherein the beam assemblyfurther comprises a supporting rod, the supporting rod being disposed atthe center of the connecting portion.
 6. The calibration bracketaccording to claim 1, wherein the beam assembly further comprises anadjustment mechanism, the adjustment mechanism being configured toadjust the beam assembly to rotate around an adjustment rotation axis,the adjustment rotation axis being parallel to the length direction ofthe fixed vertical rod.
 7. The calibration bracket according to claim 1,wherein the beam assembly further comprises two joint mechanisms, onejoint mechanism being fixed an outside wall of the first beam portionand an outside wall of the connecting portion, and the other jointmechanism being fixed on an outside wall of the second beam portion andthe outside wall of the connecting portion; wherein either of the twojoint mechanisms comprises: a fixing member, a second fixing member, arotating shaft and a fastening structure; wherein the first fixingmember and the second fixing member are pivotally connected through therotating shaft; wherein the fastening structure is located on one sideof the connecting portion, and the first fixing member, the secondfixing member and the rotating shaft are located on the other side ofthe connecting portion; wherein the fastening structure comprises afirst fastener and a second fastener, the first fastener being disposedon the connecting portion, the second fastener being disposed on one ofthe first beam portion and the second beam portion; wherein the firstfastener is hinged to the connecting portion, and the first fastenercomprises a pulling portion and a hook rod; wherein the second fastenercomprises a fastening portion; and wherein the hook rod is configured tobe fastened to the fastening portion when one of the first beam portionand the second beam portion is in contact with the connecting portion,and the pulling portion is configured to be pulled to separate the hookrod from the fastening portion.
 8. The calibration bracket according toclaim 1, wherein the stand assembly further comprises a limitingmechanism, the limiting mechanism being configured to stop the movablevertical rod moving at a certain height.
 9. The calibration bracketaccording to claim 8, wherein the limiting mechanism comprises: alimiting member sleeved on an outer wall of the movable vertical rod;and a flange disposed on an inner wall of the fixed vertical rod, theflange being close to the top of the fixed vertical rod; wherein, thelimiting member abuts against the flange to stop the movable verticalrod moving.
 10. A calibration bracket, comprising: a base; a standassembly fixedly connected to the base, the stand assembly comprising: afixed vertical rod, the fixed vertical rod being fixedly mounted to thebase; a movable vertical rod, the movable vertical rod being arranged inthe fixed vertical rod and being capable of moving only along a lengthdirection of the fixed vertical rod relative to the fixed vertical rod;and a driving mechanism mounted to the fixed vertical rod and configuredto drive the movable vertical rod to move only along a length directionof the fixed vertical rod relative to the fixed vertical rod; and a beamassembly mounted to the stand assembly and being configured to mount acalibration element, the calibration element being configured tocalibrate a vehicle-mounted driver assistant system, wherein the beamassembly comprises: a first beam portion, a second beam portion and aconnecting portion, one end of the connecting portion being pivotallyconnected to the first beam portion, and the other end of the connectingportion being pivotally connected to the second beam portion; wherein,the first beam portion and the second beam portion are able to be foldeddownward when the calibration bracket is not in use, and the first beamportion, and the second beam portion and the connecting portionconstitute a beam when the calibration bracket is in use; and wherein,the connecting portion is mounted to top surface of the movable verticalrod.
 11. The calibration bracket according to claim 10, wherein thestand assembly further comprises a guide mechanism, the guide mechanismbeing configured to guide the movable vertical rod to move only alongthe length direction of the fixed vertical rod relative to the fixedvertical rod, and the guide mechanism comprising: a grooved formed on atube wall of the fixed vertical rod; and a linear protrusion formed on atube wall of the movable vertical rod, the linear protrusion beingengaged with the groove.
 12. The calibration bracket according to claim10, wherein the first beam portion comprises a first guide rail and thesecond beam portion comprises a second guide rail, the first guide railand the second guide rail being disposed symmetrically relative to theconnecting portion.
 13. The calibration bracket according to claim 10,wherein the beam assembly further comprises a supporting rod, thesupporting rod being disposed at the center of the connecting portion.14. The calibration bracket according to claim 10, wherein the beamassembly further comprises an adjustment mechanism, the adjustmentmechanism being configured to adjust the beam assembly to rotate aroundan adjustment rotation axis, the adjustment rotation axis being parallelto the length direction of the fixed vertical rod.
 15. The calibrationbracket according to claim 10, wherein the beam assembly furthercomprises two joint mechanisms, one joint mechanism being fixed anoutside wall of the first beam portion and an outside wall of theconnecting portion, and the other joint mechanism being fixed on anoutside wall of the second beam portion and the outside wall of theconnecting portion; wherein either of the two joint mechanismscomprises: a fixing member, a second fixing member, a rotating shaft anda fastening structure; wherein the first fixing member and the secondfixing member are pivotally connected through the rotating shaft;wherein the fastening structure is located on one side of the connectingportion, and the first fixing member, the second fixing member and therotating shaft are located on the other side of the connecting portion;wherein the fastening structure comprises a first fastener and a secondfastener, the first fastener being disposed on the connecting portion,the second fastener being disposed on one of the first beam portion andthe second beam portion; wherein the first fastener is hinged to theconnecting portion, and the first fastener comprises a pulling portionand a hook rod; wherein the second fastener comprises a fasteningportion; and wherein the hook rod is configured to be fastened to thefastening portion when one of the first beam portion and the second beamportion is in contact with the connecting portion, and the pullingportion is configured to be pulled to separate the hook rod from thefastening portion.
 16. The calibration bracket according to claim 10,wherein the stand assembly further comprises a limiting mechanism, thelimiting mechanism being configured to stop the movable vertical rodmoving at a certain height.
 17. The calibration bracket according toclaim 16, wherein the limiting mechanism comprises: a limiting membersleeved on an outer wall of the movable vertical rod; and a flangedisposed on an inner wall of the fixed vertical rod, the flange beingclose to the top of the fixed vertical rod; wherein, the limiting memberabuts against the flange to stop the movable vertical rod moving.
 18. Acalibration bracket, comprising: a base; a stand assembly fixedlyconnected to the base, the stand assembly comprising: a fixed verticalrod, the fixed vertical rod being fixedly mounted to the base; a movablevertical rod, the movable vertical rod being arranged in the fixedvertical rod and being capable of moving only along a length directionof the fixed vertical rod relative to the fixed vertical rod; and adriving mechanism mounted to the fixed vertical rod and configured todrive the movable vertical rod to move only along a length direction ofthe fixed vertical rod relative to the fixed vertical rod; wherein thedriving mechanism comprises a rack, a gear reduction assembly and ahandle, the rack fixedly mounted to the movable vertical rod and beingdisposed along the length direction of the fixed vertical rod relativeto the fixed vertical rod, the gear reduction assembly being engagedwith the rack, and the handle being configured to drive the gearreduction assembly to make the rack move; wherein the gear reductionassembly comprises: a worm mechanism comprising a worm and a worm gear,the worm is fixedly mounted to the handle, and the worm gear beingengaged with the worm; and a transmission gear separately engaged withthe worm gear and the rack; and a beam assembly mounted to the standassembly and being configured to mount a calibration element, thecalibration element being configured to calibrate a vehicle-mounteddriver assistant system, wherein the beam assembly comprises: a firstbeam portion, a second beam portion and a connecting portion, one end ofthe connecting portion being pivotally connected to the first beamportion, the other end of the connecting portion being pivotallyconnected to the second beam portion; wherein, the first beam portionand the second beam portion are able to rotate downward relative to theconnecting portion; and wherein, the connecting portion is mounted totop surface of the movable vertical rod.
 19. The calibration bracketaccording to claim 18, wherein the handle and the worm are configured torotate together around a first rotation axis and the transmission gearis configured to rotate around a second rotation axis, the firstrotation axis being perpendicular to the second rotation axis.
 20. Thecalibration bracket according to claim 18, wherein the worm mechanism isconfigured to be self-locking so that the movable vertical rod is ableto be fixed at a desired position.